Question 1072056
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<U>Solution 1</U>  (two equations)

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The system of equation is

  x +   y =   80,     (1)   (where x = weight of the large box . . . )
70x + 50y = 5100.     (2)


Solve it by the Substitution method.
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<U>Solution 2</U>  (one equation)


<pre>
70x + 50*(80-x) = 5100.
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